condition mean min max ZT0-3 0.25295966666666664 0.1751945 0.36782899999999996 ZT4-7 0.24693700000000002 0.24693700000000002 0.24693700000000002 ZT8-11 0.2124255 0.2124255 0.2124255 ZT12-15 0.31887875 0.3045515 0.333206 ZT16-19 0.3260305 0.3260305 0.3260305 ZT20-23 0.6592405 0.6592405 0.6592405